In the satellite communications (SATCOM) infrastructure, both space-borne and heterogenous space-terrestrial systems will require assured connection capabilities, enhanced defensive control, and robust performance to support complex collaborative missions.
Wideband geosynchronous orbit (GEO) SATCOM can provide high-capacity and large coverage for various terrestrial applications, industry operations, and interested users. GEO SATCOM continuous operations in the open wireless environment with interferences including unintentional interferences and intentional interferences are critical to individual, cooperation, and government operations.
Each GEO satellite provides services in both the X and Ka frequency bands, with the capability to cross-band between the two frequencies onboard the satellite. It features an electrically steerable and phased array X-band, a mechanically steered Ka-band, and a fixed earth-coverage X-band. These wideband SATCOM networks entail extreme complexity, operating environment unpredictability, and interferences susceptibility.
Therefore, it is essential to develop cognitive system and dynamic spectrum management solutions that are not only context-aware and capable of learning and probing for subscriber distributions, quality of services, mission priorities and traffic patterns, but also agile in waveform adaptations to provide active countermeasures for ubiquitous persistent and adaptive RF interferences (RFI).
In addition, to provide accurate and reliable performance evaluation results to guide cognitive spectrum SATCOM development, abstracted system models must be built practically to evaluate various important techniques, including frequency-hopping spread spectrum (FHSS), channel coding, and anti-jamming capability. The practical models include FHSS and unified interferences model including unintentional and intentional RFIs. The performance evaluation metric is unified system spectrum efficiency and system energy efficiency.